A Tesla Megapack in Moss Landing, California
Andrew Evers | CNBC
At least one Tesla Megapack fire broke out early Tuesday morning at the energy storage facility operated by PG&E in Monterey, California.
As of late Tuesday morning, there were no blackouts for PG&E customers, nor any injuries to staff on site due to the fire, according to PG&E spokesperson Jeff Smith. Smith said in an email that the California facility learned of the fire at 1:30 a.m. on September 20, 2022.
PG&E commissioned the 182.5 MW Tesla Megapack system, known as the Elkhorn Battery at Moss Landing, in April of this year.
Giant batteries such as Megapack, as well as those manufactured by ABB and Northvolt, enable network operators to transfer additional capacity between provinces or states, ensuring that power from intermittent sources can be stored and used when demand is highest, or when there are unplanned outages in transport network.
Fires in energy storage systems at Moss Landing are reminiscent of accidents involving Tesla Megapacks in Australia. It also emphasizes the challenges of adopting new technology to improve the efficiency of the power grid, and to increase the utilization of electricity from renewable and intermittent resources such as wind and solar energy.
There are two distinct energy storage projects at Moss Landing in Monterey. One is operated by PG&E and the other by Texas-based Vistra. On Tuesday, a Vistra spokesperson told CNBC that their facilities were not affected by the event. However, the Vistra side of Moss Landing has had two hectic incidents in the past.
The California Highway Patrol closed a section of Highway 1 and redirected traffic away from the facility for hours after the fire.
John Haslinger, the North Monterey County Fire captain, told CNBC late Tuesday that two companies and four fire engines responded to the accident beginning at 1:40 a.m.
Firefighters used water hydrants and a water supply installed in the facility, and worked to prevent flames from spreading to the batteries and adjacent structures in the larger system. By 11:00 a.m. local time, firefighters had shut off the water but some stayed on site overnight to ensure the system did not flare up again.
“We let the initial Megapack burn,” he explained according to protocols recommended by PG&E and Tesla for the fire department. “It is too early to know the cause of the fire,” he added, but an investigation would follow in the coming weeks.
Some residents near the Elkhorn Battery substation in Moss Landing have been advised to shelter in place, keeping windows and ventilation systems closed, due to emissions after the fire. That warning was still in effect late Tuesday.
According to Richard Steadman, air pollution control officer for the Monterey Bay Air Resources District (MBARD), lithium-ion battery fires can emit toxic components, including hydrochloric acid and hydrofluoric acid. He said MBARD does not have any immediate data on air quality effects from the Elkhorn Battery fire, but will work with local authorities to study the problem after the fire is completely extinguished.
PG&E’s Jeff Smith noted that “the facility’s safety systems operate as designed when a problem is detected, automatically disconnecting the battery storage facility from the electrical grid.”
Correction: Previously, Vistra’s energy storage systems at the Moss Landing site were extremely hot.